Rock-grab.



T. L. DUROCHER;

ROCK GRAB.

APPLlCATlON FILED OCT. 16. 1916.

1,216,423. Patented Feb. 20,1917.

2 SHEETS-SHEET l.

T. L. DUROCHER.

ROCK GRAB.

APPLICATION FILED on. 16. I916.

LQWAQS. I W Patented Fe b.2(),1917.

2 SHEETS-SHEET 2.

i I m THOMAS L. DUROCHER, OF SAULT STE. MARIE. MICHIGAN.

ROCK-GRAB.

Specification of Letters Patent.

Patented Feb. 2o, iaiv.

Application filed October 16, 1916. Serial No. 125,818.

To all whom it may concern:

Be it known that LTI-IOMAE; L. Dunoormn, a citizen of the United States, residing at Sault Ste. Marie, county of Chippewa, State of Michigan, have invented certain new and useful Improvements in Rock-Grabs; and I do hereby declare the following to be a :full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to rock grabs.

I am aware of the fact that there have been many machines on the market which are designed for moving rocks. These machines, however, have only been useful in moving small rocks and it has not been possible to utilize them for moving rocks of any considerable size, owing to the principle of construction and to the formation of the various parts.

It is, therefore, the primary object of this invention to provide arock grab which is so constructed that rocks of considerable size, in practice up to forty tons, may be readily moved and so that it will be strong and durable in its construction.

A still further object of the invention re sides in so constructing the device that the grab arms will be arrested in their movement to operative and inoperative positions at predetermined points.

In the drawing Figure 1 is an elevational view showing the grab arms in their closed position;

Fig. 2 is a similar view showing the grab arms in a partially open position; and

Fig. 3 is a plan view of the bottom head.

The embodiment of the invention dis closed in the drawing includes a bottom head 1 which is provided with a plurality of pairs of spaced ears 2 which are connected together by a vertically disposed flange 3 and horizontally disposed Webs 4, the webs and flanges being formed integral with the ears and with each other. Pivotally moun ed between the members of the pairs of ears on bolts 5 are grab arms 6, which are of a general triangular form and which are provided with recesses 7. The provision of each of these recesses results in the formation of a shoulder 8 and a second shoulder 9 which extends substantially at right angles to the former shoulder. Pivoted within these recesses 7 on suitable bolts 10 are closing arms 11 which are of general I form positions, and

between their ends. These closing arms 11 are pivoted between ears 12 of the top head 13, which head is of the same general construction as the bottom head 1, having flanges 14: and webs 15. of each 01" the closing arms 11, beyond its pivot point, is a nose 16 which is located within the recess 7 and is arranged to engage the adjacent slloulder 9 to limit the movement of the grab arms in one direction. A sheave 17 is mounted. on a pin 18, which pin is carried by a pair of spaced bearing members 19 formed on and extending upwardly from the bottom head 1. A clevis 20 mounted on this pin 18 and to this clevis, one end of a chain 21 is secured, which chain passes o er a sheave '22 carried by and depending from the top head 12. This chain passes around the sheave 17, being guided by a keeper 23 which is formed on the bottom head and thence passes upwardly through the top head 12, bearing at this point against a sheave 24 which is carried by the top head. The end of the opening chain is attached at 25 to the central portion of the top head.

It will be obvious that grab arms 6 will be opened and closed by the movement of the heads 1 and 12 to and away from ecah other, which movement is caused by the operation of the chain 21. When the grab arms 6 move to their operative or closed positions, the shoulders 8 will contact with the adjacent sides of the closing arms 11, and, consequently, arrest the movement of the grub arms at the proper points, so that the arresting oi the movement will not depend upon the engagement oi the ends of the grab arms. Furthermore, the noses 16 which are formed on the ends of the closing arms 11 will engage the shoulders 9 when the grab arms are swung to their open or inoperative positions and will arrest the movement of the arms at the proper points.

It will be obvious that the construction of the rock grab is such that it will be exceedingly durable and strong and will, consequently, withstand the .wear and tear to which it is constantly subjected during the handling of large rocks and boulders. It {will also be obvious that the grab arms will have definite movements in each direction, that is to say, to and from their operative that the construction of the device is such that it will withstand the in operation, the

At the lower end a shocks incident to the arresting of the movements of the grab arms.

V '7 What I claim is 1. In a rock grab, the combination with ahead, of a plurality of grab arms carried thereby, and closing arms positively connected With and pivoted to the grab arms and constructed and arranged to limit the movement of the latter in both directions by direct contact therewith.

2. In a rock grab, the combination with a head, of a plurality of grab arms pivoted thereon, a second head, means for varymg Copies of this patent may be obtained for the distance between the heads, and closing arms pivoted to the last-mentioned head and to the grab arms, the said grab arms having shoulders thereon arranged to engage the inner faces of the closing arms to limit the movement of the grab arms in one direction and having shoulders arranged to engage noses on the ends of the closing arms to limit the movement of thc grab arms in the other direction.

In testimony whereof I aflix my signature.

THOMAS L. DUROCHER.

Washington, D. C. 

